An anonymous reader writes: T-Mobile USA will stop selling its older and cheaper limited-data plans to postpaid customers, shifting entirely to its new "unlimited" data plans that impose bandwidth limits on video and tethering unless customers pay extra. To ease the transition, T-Mobile will offer bill credits of $10 a month to customers when they use less than 2GB per month. T-Mobile began its shift to unlimited data plans in August with the introduction of T-Mobile One, which starts at $70 a month. While there are no data caps, customers have to pay a total of $95 a month to get high-definition video and mobile hotspot speeds of greater than 512kbps. The carrier said in August that the unlimited plan would be "replacing all our rate plans," including its cheaper plans that cost $50 or $65 a month. Nonetheless, T-Mobile kept selling limited postpaid data plans to new customers for a few months, but yesterday CEO John Legere said that as of January 22, T-Mobile One will be the "only postpaid consumer plan we sell." Existing postpaid customers can keep their current plans. For new customers, T-Mobile will presumably keep selling its prepaid plans that cost $40 to $60 a month and come with 3GB to 10GB of data. T-Mobile also said yesterday that it will start including taxes and fees in its advertised rate when customers sign up for new T-Mobile One plans and enroll in automatic payments, essentially giving subscribers a discount. "The average monthly bill for a family of four will drop from $180.48 to $160, according to a company spokesman," The Wall Street Journal reported.